Method of making cloth stencils



March 29 1927'.

R. TULL METHOD OF MAKING CLOTH STENCILS Filed June 28, 1926 Sheets-Sheet1 1,622,747- March 29, 1927, R TULL METHOD OF MAKING CLOTH STENCILSFiled June 2 1926 2 Sheets-Sheet 2 r ll III my Jnontot Patented Mar. 29,1927.

UNITED'STATES PATENT OFFICE.

ROGER TULL, 01 L08 ANGFLES, GALIFORNTIA, ASSIGNOR TO WESTERN LITHOGItAPHCOMPANY, 01 LOS ANGELES, CALIFORNIA, A COBPOBATIONOI CALIFORNIA.

METHOD MAKING CLOTH STENCILS.

Application fled June 28,

An ob ect of the invention is to lessen the v expense of making stencilsof this character.

A further object is to eliminate some of 10 the free-hand drawing thatheretofore has been "necessary in the preparation of stencils of thistype.

A still further'object is to enable the production of very smalllettering and fine detail work in designs, this being heretoforeimpossible of achievement with oil paint procemes.

a It is at present customary in the photo-i.

graphic method of making cloth stencils, through which aint is forced,for the artist to make a b ack and white drawing for each color of paintthat is to be employed, the drawings pre sired by the artist beingdifierent and eac drawing showing only those portions that are to beprinted in a particular color. These drawings are made upon transparentsheets oi paper laid over the colored original. Thus, there is involveda considerable amount of costly hand work. The drawings thus made arethen photographed; Another common method at present in use is for theartist to block out each stencil cloth screen by' hand from the originalsketch. This, of course, also involves a considerable amount of costlyhand work. By this new method, when the negative 1s made by hand, theartist need only pre pare one such negative ona sheet of transarent'celluloid, or similarsubstance, which is laid upon the colored original,and the artist with. a brush and suitable opaque paint copies upon thetransparent celluloid, the'original drawing. The celluloid draw- 45 mg,which actually constitutes a negative, thus made, is simply a silhouetteor flat tone line drawing. The photographic method of preparing thenegative is accomplished by the usual photographic: process,

the -.colored original being photographed on a sensitized plate, theexposed plate developed, and said plate then fixed. It is the artistswork that is so expensive in the preparation of stencils, of thischaracter and upon paper or other suitable 1928. Serial No. 118,040.-

the more of this work that can be eliminated, the cheaper the stencilscan be made. Other objects and advantages will appear 111 the subjoineddetailed description. Y

The accompanying drawings illustrate the results of certain operationsof the method embodying the invention: Figure 1 representsthe coloredoriginal whic is to be reproduced. I Figure 2 represents one of thenegatives made by copying the colored original. A printed transparencyis also shown applied to the negative. V

Figure 3' represents the printed transparency shown applied in place onthe negative in Figure 2.

. Figure 4 represents a print made. photographically on bolting clothfrom the negative in Figure 2. I

Figure 5 represents a screen produced by the artist blocking out withlacquer the portions of the print shown in Figure 4 that are to beimpervious to the paint.

Figure 6 represents another screen made inthe same manner as that shownin Figure 5 by the use of another such print as shown in Figure 4;

Figure 7 represents the result of forcing paint through the screen shownin Figure 5 v material.

Figure 8 represents the result of forcing paint through the screen shownin Figure 6, upon paper or other material already printed in one color,as shown in Figure 6. i

It will be readily understood thatthe different views mentioned above donot perfectly represent the results of the various operations because ofthe limitations imposed by representing wash drawings with linedrawings. The drawings are only apnroximations of the results secured byvarious operations. and the different colors in the colored original areindicated by lines extending in diflerent directions.

In order to perform the method, a drawing or print is used an the samepreferably appears in the colors that are to be reproduced and suchdrawing or print is herein termed colored original. The orig- .inal incolor is represented in Figure 1 of ms the drawings and in thisinstance, for example, the horizontal lines indicate the color llue, thevertical lines indicate the color red, and. the combination of verticaland horizontal lines indicates gray or black. The colored original maybe in solid colors or may be a line drawing. A negative, as indicated inFigure 2, is made from the colupon the transparent plate the coloreddrawing therebeneath. The drawing thus made is simply a silhouette orfiat tone drawing. When the negative is made by the usual photographicprocess, the colored original is photographed on a sensitizedtransparent plate, the exposed plate developed and then fixed. v

Aftepnthe negative is prepared as de shribedabove, a plurality ofphotographic prints aremade on light-sensitized bolting cloth from saidnegative, one for each color ot the original drawing or each color thatistobe reproduced. In the instance illustrated, to reproduce the coloredoriginal shown in Figure 1, it would be necessary to make three printsfrom the negative, one for the blue color, one for the red color, andone for tne black or gray. Une such print is represented in Figure 4:and it will be readily understood that the others are simply duplicatesof the one represented.

The photographic prints mentioned above may be made as follows: No. llXXbolting cloth is stretched over the edge of a wooden ltrame andthe cloththus stretched is taken to a dark room, and a camel hair brush isemployed for covering the bolting cloth on the outer side with asolution made as follows: 90 grains of bichroniate of ammonia isdissolved in 5 ounces of distilled water drops of aqua ammonia added andthis mixture will be identified as mixture G. Metal mustnot touch thesolution nor should it be exposed to any except red light. After thesensitizer thus made has been applied to the bolting cloth and hasdried, the dryin taking about an hour, the sensitized 'clot 1S ready forprinting from the negative.

For printing, the negative will be placed in close contact with thesensitized bblting cloth and then exposed, sayfor 5 minutes in front oftwo 500 watt lamps. After thus exposing, the negative is removed andthe.

bolting cloth thus exposed is washed under tlompressed air will be usedto free the clear portions of the bolting cloth of the water. Thoseportions of the sensitizer rendered insoluble in water by the action oflight will not be washed off.

After this treatment, the printed bolting cloth will be placed in thesunlight until the sensitizer that remains hardens. This takes about 10minutes; If there is no sunlight, it should dry in a place free fromdust.

The artist next blocks out with lacquer upon each of thebolting clothprints those portions that are to be impervious to the paint emplo ed inmaking the particular color run with the screen thus produced. Theresulting screens are indicated in Figurea 5 and 6, the one in Figure 5being for the red color run and the one in Figure 6 being for the bluecolor run. The screen for the black or gray reproduction is notillustrated, since it will be readily understood that in preparing suchscreen, the artist will block out with lacquer all portions that are notto appear in black or gray, leaving all portions blank or clear that areeventually to appear in the reproduction in blacl: or gray. Tn blockingout, the artist has followed out this procedure in making the screensshown in Figures 5 and 6, as in the screen illustrated in Figure 5, hehas blocked out only those portions that are eventually to appear inblue and blank, leaving blank the portions that are to appear in red.Also in Figure 6, he has blocked out only those portions that are toappear in red and black,

leaving blank or clear those portions that are to appear in blue. Thus,the screens shown in Figures 5 and 6 are exactly the reverse of oneanother. I

After the screens have been prepared in this manner, they will betreated with lacquer mixed with No. 206 Zapon blue and No. 16 Zaponthinner, or other suitable nitrocellulose roducts. This solution isapplied /on one side of the screen with a large brush and, at the sametime, the other side of said screen is rubbed with a soft rag.

The stencil screens are now ready for use in a manner well understood inthe art relating to the printing of cloth stencils of this character.Briefly, paper or cardboard will be placed beneath the stencil screensand paint will be forced through said stencil screens by application ofa squeegee to the back of the screen, the screens being usedsuccessively to make the color runs in rotation.

In order to reproduce relatively small letters, such as form, forexample, the words iRadio tube, as indicated in the drawings, it ispreferable to perform the following operations: The negative indicatedin Figure 2, if made by the artist, will omit the fine letterin Radiotube and said words will be running water to wash out the gluesolutiompr' to on a strip 9, shown in Figure 3, of

I celluloid or equivalent thin transparent substance and said printedstrip will then be secured by'a transparent glue or adhesive on thenegative in the position that it is desired the lettering is to appearin the final reproductions." The strip 9 is shown in place in Figure 2.Obviously, the print indicated in Figure4 and the screens indicated inFigures 5 and 6 will contain the words shown on the strip 9, since thelight rays will be obstructed by the letters printed on said strip.

In many instances, it is of advantage, especially when there is smalldetail in the design, to allow a color to overlie a portion of anothercolor, and, consequently, in such event some portions of the screen maybe left open even though such open portions correspond in position withthe colors that, are afterward to be forced through a different screen.

Iclaim:

1. The method of making stencils consisting in making a negative fromthe colored original that is to be reproduced, making a plurality ofphotographic prints on sensitized bolting cloth from said negative,

and blocking out on the several prints the portions thatare to beimpervious to paint and that correspond respectively to the differentcolors.

' 2. The method of making stencils consisting in making a photographicnegative from the colored original that is to be reproduced, making aplurality of photographic prints on sensitized bolting cloth from saidnegative, and blocking out on the several prints the portions-that areto be impervious to paint and that correspond respectively to thedifferent colors.

3. The method of making stencils consisting in laying a transparentplate over the colored original that is to be reproduced, copying inopaque paint upon the plate the colored original, making a plurality ofphotographic prints on sensitized bolting cloth from the painted plate,and blocking out on the several prints the portions that are to beimpervious to paint and that correspond respectively to the differentcolors.

4. The method of making stencils consisting in making a negative fromthe colored original that is to be reproduced, printing upon atransparent strip some of the lettering it may be desired to have appearin-the reproductions, securing the printed strip upon the negative,making a plurality of photographic prints onsensitized bolting clothfrom the negative after the printed strip has been aflixed thereto, andblocking out on the several prints the portions that are to beimperviousto paint and that cor respond respectively to the differentcolors.

5. The method of making stencils consisting n making a negative from thecolored original that is to be reproduced, printing upon a transparentstrip details not present in said original, securing the printed stripupon the negative, making a plurality of photographic prints onsensitized bolting cloth from the negative after the rinte d strip hasbeen aflixed thereto and blbcking out on the several prints the portionsthat are to be impervious to paint and that correspond respectivelytothe different colors. 6. The method of making stencils consisting inmaking a negative from the coloredoriginal that is to be reproduced,making a plurality of photographic prints on sensitized bolting clothfrom said negative, and blocking outon the several prints the portionsthat are to be impervious to paint.

7. The method of making stencils consisting in making a photographicnegative fromthe colored original that is to be reproduced,

out on the several prints the portions that are to be impervious topaint.

9. The method of making stencils consistin in making a negative from thecolored original that is to be reproduced, printing upon a transparentstrip some of the let tering it may be desired to have appear in thereproductions, securing the printed strip upon the negative, making aplural1ty of photographic prints on sensitized bolting cloth from thenegative after the printed strip has been afiixed thereto, and blockingout on the several prints the portions that are to be impervious topaint.

10. The method of making stencils consisting in making a negative fromthe col-. ored original that is to be reproduced, printing upon atransparent strip details not present in said original, securing theprinted strip upon the negative, making a Eplurality of photographicprints on sensitize bolting cloth from the negative after the printestrip has been aflixed thereto, and blocking out on the several printsthe portions that are to be impervious to paint. I

Signed at Los Angeles, California, this 19th day of June, 1926.

